Mechanical toothbrush



T. s. PETROPOULOS 3,141,465

MECHANICAL .TOOTHBRUSH July 21, 1964 2 Sheets-Sheet 1 Filed March 3, 1960 INVENTOR THOMAS S. PETROPOULOS ATTORNEYS mw I w a ///////////////V407/74747//// W/ F////fl July 21, 1964 PETRQPQULOS 3,141,465

MECHANICAL TOOTHBRUSH I Filed March 3, 1960 2 Sheets-Sheet 2 @9 a Z4 @emeea 3, Q 8 9 9 24 INVENTOR THOMAS S. PETROPOULOS ATTORNEYS United States Patent 3,141,465 MECHANICAL TGOTHBRUSH Thomas S. Petropoulos, RR. 2, Box 1, Caledonia, Wis., assignor of one-half to Nelson Pattern Company, a

corporation of Wisconsin Filed Mar. 3, 1960, Ser. No. 12,623 1 Claim. (Cl. 132-84) This invention appertains to tooth brushes and more particularly to a tooth brush having a mechanical means for supplying tooth paste to the brush bristles.

There have been many attempts in the past to provide mechanical means for supplying tooth paste to the brush bristles, however, to my knowledge all known types of mechanical devices have been either complicated and clumsy to use, do not provide the proper seal between the feeding mechanism and the tooth paste containing chamber, do not efficiently move the tooth paste to the upper surface of the bristles, or do not provide an adequate storage for the tooth paste relative to the feeding mechanism, i.e., the feeding mechanism usually takes up too much room in this type of implement.

Therefore, a primary object of my present invention is to provide a tooth brush with a mechanical means for supplying tooth paste to the brush and with the combination of brush, paste reservoir and mechanical means being so designed and arranged that an optimum paste storage capacity is available while the over-all size is so restricted that it may be carried in a shirt, coat or vest pocket.

Another important object of my invention is to provide, as a part of the mechanical means, a plunger or piston so constructed and of such material that when it is actuated to move paste onto the bristles of the brush it will not jam or cock and, acting with the inner wall of the paste container, will prevent paste leakage between that wall and the plunger.

A further object is to provide, in combination with the brush and mechanical means, a tooth paste reservoir which may either be filled with paste directly from the conventional tube container of such paste, or which will as an alternate also accommodate a pre-filled paste container of the cartridge type that may be inserted into said reservoir and from which, said mechanical means will, when actuated, supply paste to the top of the bristles of the brush in predetermined amounts.

Still another object is to provide means integral with the pre-filled cartridge which, acting with the inner wall of the brush housing or case and with the cover for the feed end of that case, secures the cartridge against both rotational and longitudinal displacement once the cartridge is placed in its operable position, thus eliminating any possibility of the cartridge collapsing as paste is used therefrom with a resultant jamming of the mechanical means.

A more specific object of my invention is to insure longevity to the wearing parts of the mechanical means by insulating parts made of dissimilar materials from contact with each other and by preventing damage to the longitudinal and radial ribs of the plunger or piston when paste must be replenished by providing for its complete removal from the brush housing with the feed end cover by having it retracted therein and thus, after replenishing the paste supply, the replacement of the feed end cover and mechanical means, including the plunger or piston, to its operable position is facilitated.

A salient feature of my invention resides in providing a novel paste feeding channel and brush bristle configuration which together direct the paste from the paste reservoir or cartridge and position it on the top of the brush bristles rather than at their base.

A further object of the invention is to provide a sim- 3,141,465 Patented July 21, 1964 ple, practical and reliable construction that is economical to manufacture, easy to assemble and positive in its operation.

With the above and other objects in view, which will more readily appear as the nature of the invention is better understood, the same consists in the novel construction, combination and arrangement of parts hereinafter more fully described, illustrated and claimed.

A preferred and practical embodiment of my invention is shown in the accompanying drawings, in which:

FIGURE 1 is an enlarged longitudinal sectional view taken on the vertical median line of the assembled components of the present invention;

FIGURE 2 is an enlarged longitudinal sectional view of the paste cartridge taken on a vertical median line of the cartridge of the present invention;

FIGURE 3 is a cross sectional view of the cartridge of the present invention taken on the line 33 of FIGURE 2, looking in the direction of the arrows;

FIG. 4 is a fragmentary plan view of the brush lid or head showing with greater clarity the relationship of the feed channel with brush configuration of the invention;

FIG. 5 is an enlarged cross sectional view taken on the line 5-5 of FIG. 1, looking in the direction of the arrows;

FIG. 6 is an enlarged vertical cross sectional view of of the plunger or piston of the present invention, shown removed from the casing or cylinder;

FIGURE 7 is a transverse sectional view through the plunger and feed cylinder taken on the line 77 of FIG- URE 1 of the drawings, looking in the direction of the arrows, and illustrating in particular how the outer periphery of the plunger or piston is compressed and completely seals;

FIGURE 8 is an enlarged fragmentary view, partly in section, showing the outer periphery of my novel plunger or piston.

Referring to the various views of the accompanying drawings in which like numerals refer to like parts, it will be observed that the housing or case 10, cylindrical in form at its feed and handle end 11 has cast integral at its opposite end a brush base 12 in which the bristles 13 are secured in a configuration and for a purpose which will hereafter be more fully described. The feed end or handle section 11 has a cover 14 removably threaded thereto for closure purposes and actuating knob 15 spaced therefrom. The inner diameter of the cover 14 is of the same size as the inner diameter of the feed end 11 of the housing 10.

It should be borne in mind that all of the component parts of my novel tooth brush are preferably made of plastic with the exception of the feed screw which is formed from metal. The steel feed screw 16 has threaded thereto the plunger or piston 17. A splined end 18 of the feed screw 16 extends through the aperture 19 of the feed cover 14 and carries the actuating knob 15. The aperture 19 is located dead center of the cover 14 and the tolerance relationship between it and diameter of the feed screw 16 is of such character that the feed screw 16 is supported thereby and also positioned centrally in the cylindrical opening of the feed end 11 of the housing 1t). The spaced relationship of the cover 14 and the actuating knob 15 is controlled and maintained by the length of the spline on the feed screw 16 which secures and carries the actuating knob 15.

As most clearly shown from the cross sectional view of the plunger 17 (note FIGURES 6, 7 and 8), I have provided on its outer periphery a plurality of equally spaced longitudinal ribs 20 and a plurality of radial serrations 21. While the spaced ribs can be of any desired nurnber, I prefer it to provide eight as shown. The

plunger 17 is cast with its ribs 20 and serrations 21 and with internal threads 22 in its aperture 23. FIG- URE 7 shows clearly the jointure of one of the longitudinal ribs 20 and one of the serrations 21. FIGURE 8 also clarifies this relationship. It has also been determined that the plunger 17 must, in order to function properly, have a greater material hardness throughout its core portion 22 and threaded aperture 23 and a lesser material hardness at its outer periphery 23. This is accomplished by using rubber compounds having the required duro-meter readings in the casting operation.

The internal wall of the cylindrical handle portion of the housing 16 has cast integral therewith the equally spaced vanes 24 which complement and, in operation, acting together with the longitudinal ribs 2%}, guide the plunger 17 in its travel in the cylindrical portion of the housing and also prevent rotational movement of the plunger 17 during its travel. It is to be noted that the vanes 24 extend to the point 25 shown in PEG. 1, which is closely adjacent to the open end of the cylindrical handle portion 11 but do not extend completely to said open end. By stopping the vanes 24 at the point 25' the insertion of the cartridge 36 as hereinafter described is more easily accomplished, since the channels 40 of the cartridge 36 and the vanes 24 can be adjusted to their complementary positions after the initial start of the cartridge 36 into the cylindrical handle portion 11 of the housing 10. The serrations 21 of the plunger 17, as the plunger is moved toward the brush end of the housing 10 wipe the internal wall of the cylindrical portion of the housing 10 and prevent leakage of the paste between that wall and the outer periphery of the plunger 17. This can be accomplished only when the proper tolerance is maintained between the diameters of the cylindrical opening of the housing 10 and the plunger 17, and when the durometer hardness of the serrations 21 is such that those serrations can be slightly compressed during the travel of the plunger 17 (note FIGURE 7 in particular).

Referring now to the cover 14 illustrated in FIGURE 1 of the drawings, it is to be noted that the internal construction thereof provides the spaced vanes 25. The vanes 25 are spaced in the same manner as the vanes 24 of the cylindrical handle portion 11 of the housing 10 and are of the same size. They act as a stop in positioning the cover 14 to the housing 10 and when the plunger 17 is retracted into the bore of the cover 14, by turning the actuating knob in a counter-clockwise direction, the serrations 21 of the plunger 17 are maintained in their compressed position. The importance of this feature becomes apparent when it becomes necessary to replenish the paste supply since, with the plunger 17 retracted into the bore of the cover 14 the serrations 21 of the plunger 17 are held compressed by the vanes 25. If the serrations 21 were permitted to expand upon the plunger being retracted into the cover 14 they would be damaged in repositioning the plunger in the cylindrical handle portion 11 of the housing 10 after the paste supply had been replenished. Also the wiping and sealing properties of the serrations 21 would be destroyed and paste leakage would occur.

Adjacent to the closed inner end of the cover 14 is a polyethylene washer 26, seated and held in a notched shoulder in the metal feed screw 16. The washer carries the thrust of the turning of the feed screw 16, insulates the feed screw 16 from excessive contact with the inner end wall 14" of the cover 14, and since wear does not occur between plastic parts as it would between metal and plastic parts, the washer 26 adds materially to the operable life of this invention.

The outer end wall of the actuating knob has a fluted contour 15' which provides an easily held finger grip for use in rotating that knob.

The brush end of the housing 10 is enclosed by the cap 27, which is cylindrical at its open end and which may easily be placed in or removed from its functional position. The inner diameter of the cap 27 and the housing 11) outer diameter'cornplement each other in this respect. A carrying clip 28 and moisture vent holes 29 are also provided for the obvious purposes.

As the cylindrical portion of the housing 119 extends toward the brush end 12 thereof, its diameter is substantially reduced and internal shoulders are formed as at 30 which stop the travel of the plunger 17 at that point. The internal section of the housing 10 from the open cylindrical end 11 to the shoulders 30 is defined as the tooth paste reservoir 31 of this invention. The inner wall contour of the housing 10 also forms the passageway 32, which is in effect a continuous or extension of the reservoir 31. The passageway 32 terminates at the abutment 33 which is angularly projected on the brush base 12, as at 34, and through which a feed hole or discharge channel 35 of a defined size is drilled or cored, to provide a channel through which the paste of the reservoir 31 and its extension 32 may be fed onto the bristles 13.

From the foregoing, it should be obvious that it is merely necessary to remove the cover 14 after the plunger has been retracted and fill the tooth paste reservoir 31 with tooth paste from an ordinary tooth paste tube, however, it should be noted that, if desired, the implement may be refilled by providing a cartridge which contains a new supply of paste. Therefore, the cartridge 36 is cylindrical in form, is suitably capped at its ends and is of a diameter and length that will permit it to be inserted into the paste reservoir 31. Before such insertion, the end caps 37 and 38 respectively, are removed. As shown in FIGS. 2 and 3, internal vanes 39 are provided which act in the same manner as the vanes 24 of the housing 10 previously described, to prevent rotation of the cartridge and/or rotation of the plunger 17. In fact, the inner channels 40 of the vanes 39 receive the peak ends of the vanes 24 located in the feed end 11 of the housing. This cartridge 36 is provided at one end with a peripheral flange 41 and this flange is provided with diametrically opposite slots or openings 42 and 43 respectively. These slots are to receive the inwardly directed tab members 44 and 45 formed on the end cap 38. Obviously, in order to remove the end cap 38, it is merely necessary to align the slots 42 and 43 with the tabs 44 and 45 to remove the cap from the cartridge end. Further, to apply the cap, it is obvious that the procedure is merely reversed and the tabs 44 and 45 are aligned with the slots 42 and 43, the cap pushed inwardly and then rotated, whereby it will be firmly held to the cartridge.

To assemble the components of this invention and prepare it for operation, the feed screw 16 has the actuating knob 15 secured thereto by pressing it onto the splined end thereof. The opposite end of the feed screw is then passed through the aperture of the cover 14, the washer 26 is installed in its proper position on the feed screw 16 and the plunger 17 is threaded thereto and retracted into the vaned bore 25. The reservoir 31 is filled with tooth paste, or alternately, the cartridge 36 is inserted therein. The free length of the feed screw is positioned in the paste reservoir 31 and its extension 32, or alternately the cartridge 36 and the passageway 32, the cover 14 is threaded to the housing 10 and by rotating the actuating knob 15 in a clockwise direction the plunger 17 is advanced toward the brush end of the housing 10 forcing paste from the reservoir 31, the passageway 32, through the feed hole 35 and onto the bristles 13.

To replenish the paste supply, the actuating knob 15 is turned in a counter-clockwise rotation, retracting the plunger 17 into the cover 14. The cover 14 and the feed screw 16 are then removed from the housing It at its handle or feed end 11. The reservoir 31 is again filled, either directly, or with a new cartridge 36. The feed screw 16 is positioned, the cover 14 secured to the hous ing 10 and the actuating knob 15 turned in a clockwise direction until paste is again forced onto the bristles 13 of the brush.

It is in operation that the importance of the relationship of the components of this invention becomes readily apparent. The number of turns of the actuating knob 15, necessary to supply a suitable amount of paste for the tooth brushing operation, is determined by the travel of the plunger 17 and the travel, in turn, by the pitch and thread of the feed screw 16 and the complementary internal threads of the bore of the plunger 17. In the brush of this invention these relationships are so defined that between one-quarter and two turns of the actuating knob 15 will supply the amount of paste, from minimum to maximum, and to suit the vagaries of the user, onto the bristles of the brush. In other words, the thread 16 of the feed screw 16 are what may be termed as fast threads.

To direct and assure paste being forced to the top of the bristles of the brush, the feed hole 35 is drilled or cored through the abutment 34 at not less than a thirtydegree angle, the hole size is restricted to not more than .060 to assure a concentrated pressure on the paste and the spacing of the tufts of bristles, as appears in FIG- URE 4, is of such character as to direct the paste to the top of the bristles where it is most desirable to have it.

In conventional bristles spacing, it is normal practice to position four rows or tiers longitudinal of the brush base with equal spacing therebetween. In the present invention, conventional spacing is followed on the brush base 12 forward of the abutment 33 as projected at 34. At the sides of the abutment 33 as projected at 34, the spacing of the bristle tufts is maintained on the same center lines in the outer rows 50 but to avoid collapsing the walls of the feed hole or channel 35 the staggered configuration shown in FIGURE 4 must be resorted to in order to also obtain proper bristle density. Likewise, the spacing of a bristle tuft 51 directly at the opening of feed channel 35 on the brush base 12 assures that it will, in conjunction with the concentrated paste pressure, obtained as noted, direct the paste to the top of the bristles 13.

The paste reservoir 31 and the passageway 32 and the small space displaced by the feed screw 16, combine to give a maximum paste storage capacity so that a substantial number of brushings may be had before paste replenishment becomes necessary.

It is to be understood that while a preferred embodiment of this invention has been shown and described,

various modifications thereof may occur to those skilled in the art and it is intended that no limitation be placed on the invention except as defined by the scope of its claim.

I claim:

A toothbrush having a hollow paste containing handle section, a brush body carrying brush bristles thereon on one end of said handle section, said brush body having a passageway communicating with said hollow handle section and with said brush bristles, a feed mechanism for said hollow paste containing handle section including, a longitudinally extending feed screw positioned centrally in said hollow paste containing handle section, an end cover threaded on the handle section adjacent the end opposite to said brush body, said cover carrying and supporting said feed screw, an actuating knob carried by said cover secured to said feed screw and adapted to rotate the same, a resilient plunger having internal threads receiving said threaded feed screw, a series of longitudinally extending spaced vanes within said hollow paste containing handle section, said plunger having an inner core portion of a greater material hardness than its outer periphery, and said outer periphery of said plunger being formed with a plurality of radial serrations and a plurality of equally spaced longitudinal ribs cooperating with said vanes to prevent rotation of said plunger, the outer periphery of said plunger abutting the inner surface of said hollow paste containing handle section and being compressed to completely seal the same, whereby actuation of the knob will move said plunger in said container for forcing paste onto the brush bristles, said cover having an extended internal bore of a size and configuration to completely receive said plunger in its retracted position and maintain its sealing surface in a compressed status, whereby said cover, actuating knob, feed screw and plunger may be removed from said hollow paste containing end for refilling of the same.

References Cited in the file of this patent UNITED STATES PATENTS 1,002,673 Goodwin et al Sept. 5, 1911 1,471,330 Farmer Oct. 23, 1923 1,485,022 Fesler Feb. 26, 1924. 1,711,183 Smith -1 Apr. 30, 1929 1,953,296 Gleeson Apr. 3, 1934 2,962,032 Reuter Nov. 29, 1960 

